Detergent builder composition

ABSTRACT

THE PRESENT INVENTION RELATES TO A DETERGENT FORMULATION HAVING A BUILDER WITH THE FORMULATION:   NA-OOC-CH2-CH(-SO3-NA)-COO-NA

United States Patent Ofifice 3,798,183 Patented Mar. 19, 1974 3,798,183DETERGENT BUILDER COMPOSITION Herman A. Bruson, Woodridge, Conn., andHenry Gould, Houston, Tex., assiguors to Milchem Incorporated, Houston,Tex. No Drawing. Filed Aug. 20, 1971, Ser. No. 173,654

Int. Cl. C11d 1/14, 1/22 US. Cl. 252-557 1 Claim ABSTRACT OF THEDISCLOSURE The present invention relates to a detergent formulationhaving a builder with the formula:

S;Na NaOOC-CHa--COONQ.

BACKGROUND OF THE INVENTION (1) Summary of the invention.--The presentinvention relates to the use of sodium sulfosuccinate as a builder foranionic detergent formulation.

(2) Description of the prior art-The broad concept of built detergentcompositions has been known for some time and encompasses the capabilitypossessed by certain substances of substantially improving theeffectiveness of detergent compounds. The improved or enhanced result asevidence by a washed article appearing cleaner and brighter is generallycharacterized as the builder efiect. Compounds which perform in thismanner are called builders. The improved performance attributed to thebuilder is manifested in a variety of ways. Among the ways with respectto which builders are thought to have useful effects are such factors asstabilization of suspended solids soils, emulsification of soils, thesurface activity in an aqueous detergent solution, the solubilization ofwater-insoluble materials, foaming or suds producing characteristics ofthe washing solutions, peptization of soil agglomerates, neutralizationof acid soils and the like, in addition to the sequestration of mineralconstituents present in the washing solution. The term detergent is usedin a general sense and is intended to embrace both cleaning andwhiteness maintenance properties. Built detergent compositions preparedspecifically for laundering the wide range of natural and syntheticfabrics commonly in use today are termed heavy-duty detergents. Suchcompositions rely for their effectiveness, in part, on a high proportionof builder materials being present in the composition.

The nature of the building action, while quite widely recognized in theliterature is not completely understood. There does appear to be someconnection between the ability of a builder to soften water which isused to make up the washing solution and the improved result indetergency obtained when the builder is used. However, not all materialswhich act to sequester hardness-imparting calcium and magnesium ionsperform satisfactorily as builders. No general basis has been found oris known either as regards physical properties or in chemical structureupon which one can predict with any degree of accuracy the performanceof chemicals as detergent builders. Further, useful building actionswith the most effective builders can be noted both above and below thepoint at which the builder is present in the washing solution instiochiometric proportions to the hardness in water.

Building effects in detergents have been noted in connection withvarious inorganic alkaline salts such as alkali metal carbonates,bicarbonates, phosphates, polyphosphates and silicates. Similar buildingproperties have also been noted in connection with certain organic saltssuch as akali metal, ammonium or substituted ammoniumaminopolycarboxylates such as sodium and potassiumethylenediaminetetraacetate, sodium and potassiumN-(Z-hydroxyethyl)-ethylenediaminetriaacetate, sodium and potassiumnitrilotriacetate, and sodium, potassium andtriethanolammonium-N-(Z-hydroxyethyl)-nitrilodiacetate. Alkali metalsalts of phytic acid have also been utilized to some degree as organicbuilders in detergent formulations.

In recent years, the detergent industry has become concerned about waterpollution caused by phosphates. The use of these builders is beingdiscourage or prohibited by law in order to curtail the growth of algaein rivers, lakes and streams where the residues from household andindustrial detergents can collect, causing ecological damage bymaintaining an active growth of algae that normally require phosphateions for metabolism and survival.

Sodium sulfocusccinate has been prepared by use of a variety ofreactions known to those skilled in the art. For example, US. Pat. No.3,533,944, entitled Anti-Caking Composition for Linear Alkyl ArylSulfonate Detergents, teaches a process for producing an alkalisulfosuccinate solution useful in providing anti-cacking properties todetergents by reacting an approximately stoichiometric amount of sulfurdioxide with a concentrated solution of a disodium or dipotassiummaleate while maintaining the pH of the solution within limits of 4 to11 and heating the solution between F. and 250 F. for a time sufiicientto essentially complete the reaction. The inventors also teach the useof the material in built and unbuilt straightchain alkyl benzenesulfonate detergent formulations in amounts from 2 to 25% by weight ofthe alkali benzene sulfonate component of the total detergentformulation to prevent the formation of lumps and charring and toeliminate tackiness and caking problems during processing and storage.Generally speaking, the alkyl benzene sulfonate is used in the detergentformulation typically in an amount of about 16%. Thus, the maximumamount of sodium sulfosuccinate typically used would be less than about4% of the total formulation.

It has now-been surprisingly discovered that although sodiumsulfosuccinate exhibits no builder action in anionic detergents atconcentrations below about 20%, it does provide such action when used ina range from about 20% to about 60% by weight of the entire detergentformulation. This material does not contain phosphorous or nitrogenwhich can act to enhance and maintain the growth of algae.

It is therefore an object of the present invention to provide a new andimproved class of detergent builder materials.

It is a further object of the present invention to provide a newdetergent composition.

Other objects and advantages of the present invention will be readilyapparent to those skilled in the art from a reading of the specificationand claims which follow.

DESCRIPTION OF THE PREFERRED EMBODIMENTS Sodium sulfosuccinate as usedin the present invention may be made in a variety of ways known to thoseskilled in the art and our invention is not dependent upon theparticular preparation of this material. The material may be prepared byreacting sodium hydroxide with water, resulting in an aqueous causticsolution. Maleic anhydride may then be added to the solution.Sulfonation may be achieved by then adding sulfur dioxide slowly,followed by incremental charges of sodium hydroxide to adjust the pH tothe alkaline side. Additional maleic anhydride may be added to reactwith any free sulfur dioxide. Variations of this technique such as thatdetailed in Example I, may also be utilized.

Many varieties of synthetic detergents may be built with the builder ofthe present invention. Generally speaking, any anionic detergent may besuccessfully utilized.

These detergents are water-soluble salts, especially the alkali metalsalts of sulfuric reaction products having in their molecular structurean alkyl radical containing from about 8 to about 22 carbon atoms and aradical selected from the class consisting of sulfonic acid and sulfuricacid ester radicals. Among the particular materials which can be usedare: (1) the sodium alkyl sulfates, particularly those obtained bysulfating high carbon alcohols produced by reducing glycerides of tallowor coconut oil, (2) sodium or potassium alkylbenzenesulfonates in whichthe alkyl group contains about C to about C (3) sodiumalkylpolyethersulfonates, especially those ethers of the higher alcoholsderived from tallow and coconut oil, (4) sodium coconut oil fatty acidmonoglyceride sulfates and sulfonates, (5) sodium or potassium salts ofsulfuric acid esters of the reaction product of 1 mole of a higher fattyalcohol and about 1 to 6 moles of ethylene oxide, (6) sodium orpotassium salts of alkylphenol polyoxyalkylene ether sulfate with about1 to units of alkylene oxide per molecule and in which the alkylradicals contain about 9 to about 18 carbon atoms, (7) the reactionproduct of fatty acids esterified with isethionic acid and neutralizedwith sodium hydroxide, where, for example, the fatty acids are derivedfrom coconut oil, and (8) sodium or potassium salts of fatty acid amidesof taurine in which the fatty acids are derived from coconut oil or thelike. These detergent compounds can be formulated into a variety offorms such as granular, flake, liquid and tablet forms.

Generally speaking, when preparing either granular or liquid detergentformulations, about to about 60% by weight of the total activeformulation may consist of the present builder. Under normalcircumstances, the range of about 30% to about 50% is preferred andabout 40% of our builder has been found to be generally most desirable.However, the exact amount of the builder composition of the presentinvention utilized will vary depending on the base detergent formulationand the particular commercial application at hand. The upper limit ofabout 60% is not deemed critical. However, because of economic reasons,it is believed to be a practical limit.

Our builder composition has been found to have particular utility inliquid detergents. Liquid detergents have posed especially perplexingand difiicult problems for the detergent formulators, mainly because ofsolubility and stability factors in aqueous mediums. It is well knownthat although sodium tripolyphosphate is effective in granulardetergents, it is not satisfactory in liquid formulations because ofconversion to orthophosphate. In view of the increasing acceptance bythe industry of liquid detergents it is a very significant contributionof the present invention that an improved built detergent product ismade possible that will provide good detergency action in a liquidformulation.

Most of the built liquid detergents available are either water based orhave a mixture of water and alcohol as the liquid base. Our detergentbuilder composition may be satisfactorily utilized in these bases.

A detergent formulation containing our builder composition may contain avariety of miscellaneous additives which may make the finished productmore effective and commercially attractive. For example, a solublesodium carboxymethylcellulose may be added in minor amounts to inhibitsoil redeposition. A tarnish inhibitor such as benzotriazole orethylenethiourea may be added in minor amounts. Fluorescence, perfume,coloring compounds, and optical brightening agents may be frequentlydesirable. An alkaline material or alkali such as sodium or potassiumhydroxide may be added in minor amounts for pH adjustment. Additionally,moisture and heightening agents such as sodium sulfate and sodiumcarbonate may also be added. Other minor additives may also includecorrosion and scale inhibitors and hydrotropic agents to promotehomogeneity at lower temperatures.

The following examples further illustrate the novel qualities of thepresent invention:

4 EXAMPLE I The present example illustrates a suitable laboratorypreparation for sodium sulfosuccinate. To 108 grams of maleic acid wasadded 200 cc. of water to prepare solution A. To 139 grams of sodium.sulfite was added 500 cc. of water to prepare solution B. Solution A wasadded to solution B slowly at about 40 C. An exotherm was noted. Thesolution was allowed to age overnight after which 87 grams of 50% sodiumhydroxide was added to adjust the pH to about 12. The solution containedabout 27% trisodium sulfosuccinate. The solution may be used as is ormay be spray dried, resulting in a fine powder.

EXAMPLE II The present example demonstrates the inability of trisodiumsulfosuccinate to effectively build an anionic detergent formulationwhen used at 10% by weight of the entire detergent formulation (62.5% byweight of trisodium sulfosuccinate based on the straight-chain alkylbenzene sulfonate content of the finished detergent).

Standard Tergotometer tests were made to determine the soil removaleffectiveness of a representative unbuilt laundry detergent compositionas a control formulation and 10% of the builder composition of thepresent invention in a similar formulation. This test is one commonlyused in the industry and is detailed in Proposed Method for MeasuringSoil Removal and Whiteness Retention of Fabrics, published by theAmerican Society for Testing and Materials, February 1969. This methodprovides a means of measuring the ability of detergents to removeartificial soil from fabric and prevent its redeposition on cleanfabric. A laboratory-scale agitator-type washing machine is utilized,together with a reflectometer which is calibrated by means of standardvitreous enamel plaques having reflectance in the range of the fabricsample being measured. The washer is operated at a suitable fixed speedwhich is recorded with test results. After washing, the sample materialis damp dried between clean toweling and then ironed flat between twopieces of clean white cotton sheeting. The reflectance readings are thendetermined. The test builder of the present invention was made as inExample I. The detergent compositions were as follows:

Percent by wt.

Test

Control formula.

Sodium sulfosuccinate 10. 0 Carboxymethyl cellulose- 1. 0 1.0 Sodiumsllieate 7. 0 7. 0 Sodium sulfate .4. 76.0 66. 0 Linear sodium alkylarylsulfonate. 16. 0 16. 0

Each sample was tested at a dilution of 0.25% in water having a hardnessrating of 15 grains per gallon. Detergency was measured as the increasein diffuse reflectance accomplished after the laundering of thefollowing three different soiled cloths:

(1) Test fabric soiled cotton, washed and wear finish (2) ACH soiledcotton (3) US. testing soiled cotton The calculation of the improvementin reflectance was made as follows:

Percent improvement in reflectance:

To assure the presence of the correct amount of each formula ingredientin the wash solution, dilute aqueous solutions of both samples wereprepared and added on an aliquot basis to the Tergotometer beaker.

The Tergotometer test was made in accordance with the following testconditions:

The results of soil removal tests are as follows:

TABLE 1.AVERAGE INCREASE IN DIFFUSE REFLECTAN CE U.S. Test A011 115testing fabric Total Builder cotton cotton cotton gain Control. 32. 6 5.4 15. 5 53. 5 Test formula 32. 6 5. 3 15. 3 53. 2

The results of this test indicated that the sodium sulfosuccinate levelwas inadequate to provide builder characteristics. The detergentformulation with sodium sulfosuccinate at this level was not assatisfactory as the control formulation containing no builder material.

EXAMPLE III Tests were run and results were evaluated as in Example IIabove with sodium sulfosuccinate made as in Example I at levels of and40% by weight of the entire detergent formulation. The results of thistest are given in the table below:

TABLE 2.-AVEAGE INCREASE IN DIFFUSE EFLECTANCE ACH 118. Test 115 testingfabric Total Builder cotton cotton cotton gain Control 32. 6 5, 4 15. 553. 5 Test formula (20% by wt.) 83. 5 5. 4 14. 9 53. 8 Test formula (40%by wt.) 35. 3 6. 0 17. 4 58. 7

The results of this test indicated that at the 20% by weight level,sodium sulfosuccinate provides some builder action. This action becomesmore striking as the level is increased, as exemplified in the 40% byweight level tested above.

Although the invention has been described in terms of specifiedembodiments which are set forth in detail, it should be understood thatthis is by illustration only and that the invention is not necessarilylimited thereto, since alternative embodiments and operating techniqueswill become apparent to those skilled in the art in view of thedisclosure. Accordingly, modifications are contemplated which can bemade without departing from the spirit of the described invention.

What is claimed is:

1. A process for building a detergent composition having present thereina water-soluble salt of an alkyl aryl sulfonate, which comprises addingthereto in an amount from between about forty percent (40%) and aboutsixty percent by weight of the total detergent composition, a builderhaving the formula:

SOQNa NaOOCCHz(I3-COONa References Cited UNITED STATES PATENTS 3,328,3146/1967 Marquis 252-483 3 ,424,690 1/ 1969 Marquis 252554 X 2,264,10311/1941 Tucker 21023 3,635,829 1/1972 Yang 252-526 3,661,787 5/1972Brown 252109 OTHER REFERENCES Bistline et al., JAO'CS, vol. 48, No. 2,pp. 74-76 (1971 LEON D. ROSDOL, Primary Examiner P. E. WILLIS, AssistantExaminer US. Cl. X.R.

